1. Field of the invention
The present invention relates to an apparatus for laminating a first and a second sheet.
The present invention further relates to a method for laminating a first and a second sheet.
2. Related Art
Various products are fabricated by sequential addition of components to previously supplied components. An important application area is in the manufacturing of electronic components as a stack of sheets. For the purpose of this description a sheet is an artifact that is thin relative to its length and width, e.g. a sheet of glass or a polymer sheet. A sheet may comprise a plurality of layers. The electronic product comprises for example a first sheet having OLED functionality, a second sheet comprising printed photodiodes and a third sheet comprising driver electronics. Subsequent sheets in the stack have electronic functional areas that in contact with each other perform an electronic function. In the manufacture of such electronic components it is important that mutually subsequent sheets are accurately positioned with respect to each other in order that electronic, optic or fluidic features, such as microfluidic channels in a sheet accurately contact features to cooperate therewith in the subsequent sheet.
The OPTEK DPL-24 user's guide describes a differential pressure laminator. The laminator described therein comprises a vessel having a top and a bottom section that are separated by a flexible diaphragm of silicone rubber. Each of the sections has a respective port and a respective heater. The materials to be laminated are applied on a drawer platen that is arranged in the bottom section. In a first stage of a lamination cycle air at atmospheric pressure is present in the bottom section of the vessel, pushing the diaphragm upwards, above and separate from the materials to be laminated. In a subsequent stage of the lamination cycle, both sections are evacuated via their respective port. In this stage the diaphragm still is separate from the materials to be laminated. Air is allowed to escape from between the materials to be laminated.
In a subsequent stage of the lamination cycle, pressure is applied to the port of the top-section of the vessel so that the preheated diaphragm starts to apply an isostatic pressure against the materials to be laminated.
At the end stage of the lamination cycle the port of the top-section is connected to the vacuum pump and the port of the bottom-section is vented to atmospheric pressure, so that the diaphragm releases the laminated materials and the drawer with the laminated materials can be removed from the vessel.